Water-filled building block for temporary levee

ABSTRACT

A hollow block in the form of a rectangular parallelepiped when filled with water, is joined with a plurality of similar water-filled blocks to form a flood barrier. Two opposite sides of each block have connection features that connect with features on the first and third sides of adjacent blocks to form a wall of connected blocks. Top and bottom walls of each block each have an inter-tier connection feature that mates with a block in each adjacent top or bottom wall. Each block includes on each of its top and bottom walls, inter-tier connection features structured to mate with an inter-tier connection feature of a similar block in the adjacent tier.

CROSS-REFERENCE TO RELATED APPLICATIONS

This is a regular application filed under 35 U.S.C. §111(a) claiming priority, under 35 U.S.C. §119(e)(1), of provisional application Ser. No. 61/175,582, previously filed May 5, 2009 under 35 U.S.C. §111(b).

BACKGROUND

Flooding caused by melting snow and ice has become an unfortunate fact of life for populations along northern rivers. When the threat arises, the usual procedure is to emplace temporary dikes or levees to restrain the rising rivers from flooding valuable buildings.

Four current solutions exist. One is to simply give up, and abandon sites subject to flooding. This is expensive and unpopular with the residents of these at-risk areas.

Houses are sometimes built on stilts or pilings so that the valuable portions of the structure are at all times above the highest level of flooding. This solution leads to structures with very little esthetic appeal. The necessity of climbing stairs every time one enters the occupied space is also inconvenient.

Another is to install permanent levees, which is extremely expensive. Permanent levees also destroy views of the river involved. When the river is within its banks, the view of the river is of course, an important amenity for selecting the site for the structure.

A fourth solution is to install temporary dikes or levees comprising piles of sandbags. This solution requires filling these sandbags with sand and one by one, heaping them onto each other to form the levee.

The process of filing the bags and then emplacing them to form the required dikes is extremely time-consuming, expensive, and labor intensive. People from hundreds of miles away are recruited to help with the sandbagging activities. The bags are heavy and huge numbers of them are required. For example, Fargo, N. Dak. used 350,000 sandbags to, as it turns out, successfully repel the 2009 flood on the Red River of the North.

After the river recedes, all of the bags must be removed and emptied. The sandbags themselves are usually destroyed because drying them is more expensive than replacing them.

A particularly harmful aspect of this process is the procession of heavy trucks carrying the sand from its source to the levee sites. These trucks travel over roads that are vulnerable to heavy loads and are normally subject to spring load restrictions. Often, the roads are damaged so badly as to require complete reconstruction. In addition, the process for handling the sand and sandbags requires much other heavy equipment.

It is fair to say that all of these existing technical solutions are primitive and unsatisfactory.

BRIEF DESCRIPTION OF THE INVENTION

A hollow block in the form of a rectangular parallelepiped can be joined with a plurality of similar blocks, all of which are then filled with water to form a flood barrier. The block has first through fourth sides, a top, and a bottom. The first and third sides have connection features that connect with features on the first and third sides of adjacent similar blocks to form a wall of connected blocks. The top and bottom of each of a plurality of said blocks has an inter-tier connection feature mating with one of the adjacent top and bottom of a similar block to allow stacking of a plurality of these blocks into tiers to form a flood barrier taller than the height of a single block.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a hollow block forming a container to connect to a plurality of similar blocks to form a flood barrier.

FIG. 2 is a side elevation view of two containers in different tiers that shows one form of the connecting feature between two such blocks.

FIG. 3 is an end elevation view of an improved temporary levee wall having as its components, a relatively small number of relatively large containers comprising integral or unitary blocks 11 filled with water.

FIG. 4 is a top elevation view showing the relationship between the containers in a bottom tier and a tier immediately above it, for a portion of a levee wall.

FIG. 5 is a top elevation view of a single block 11 with annotations and suggested dimensions.

FIG. 6 shows a side elevation of a levee wall comprising the blocks of FIG. 1 assembled on a sloping surface.

FIG. 7 is a side elevation view of a number of blocks assembled to form a flood barrier with a nominal 75% overlap of blocks from one tier to the next.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The invention here involves a fifth solution that has substantial cost and time advantages over every one of the other solutions.

FIGS. 1-7 show one form of the invention. FIG. 3 is an end view of an improved temporary levee wall or flood barrier 10 having as its components, a relatively small number of relatively large containers comprising integral or unitary blocks 11 filled with water. In FIG. 3, arrows from reference numbers indicate a number of components designated by that reference number. Reference numbers 12 and 16 respectively designate the dry and wet sides of levee wall 10.

FIG. 1 is a perspective view of a hollow block 11 forming such a container. Blocks 11 have connection features that bind or attach adjacent blocks 11 in a levee 10 to each other to maintain the structural integrity of the temporary levee 10.

Block 11 is in the general form of a parallelepiped having a substantially square footprint, although a rectangular footprint may also provide the necessary functionality. “Parallelepiped” in this context means a polyhedron consisting of six faces that are rectangular parallelograms.

Block 11 has an upper wall or top 17 and a floor or bottom 18. The lead line indicates an edge of floor 18. Block 11 has sidewalls 12A-12D intersecting edges of upper wall 17 and floor 18. Only the upper edges of sidewalls 12C and 12D are visible in FIG. 1.

Each sidewall 12A-12D has a connection feature 14, 20, 13, or 19 respectively and running between wall 17 and floor 18. Each connection feature 14, 20, 13, and 19 is arranged to interlock with a complementary connection feature carried on an adjacent sidewall of a block 11.

Connection features 14 and 20 comprise tenon projections of constant trapezoidal cross section. Connection features 13 and 19 comprise mortise grooves of constant trapezoidal cross section into which features 14 and 20 on adjacent blocks 11 slide to form a joint similar to that of a dovetail such as used in furniture manufacture. Features 14 and 20 should fit relatively loosely within features 13 and 19 so that a number of blocks 11 can be assembled into a levee wall 10 without binding. Other types of cross sections may provide similar results.

Each block 11 has a filler hole 27 near one corner of the upper wall 17. Sidewalls 12B and 12D near the intersections with floor 18 each have a drain plug 15. Two drain plugs are preferable for reasons to be explained.

Internally, each block 11 has stiffening walls 23 and 24 running between opposite sidewalls 12A-12D and to the top and bottom of the block 11. Opening 33 provides communication between the four chambers that stiffening walls 23 and 24 define so that water flowing into filler hole 27 distributes among all of the internal chambers. Bottom blocks 11 (FIG. 3, tier 10A) in a levee wall 10 may bear as much as 8000-10000 lb., so resistance to crushing is important.

The floor of each block 11 has at least one recess 30 that will align with a filler hole 27 when the block 11 is incorporated into a levee wall 10. A pin 37 is sized to fit into both recess 30 and filler hole 27. A flange 37 on pin 36 prevents pin 36 from falling into a block 11.

FIG. 5 is a top elevation view showing dimensions and construction details of an individual block 11. The height of block 11 may be 2 ft. and the footprint is shown as 3 ft.×3 ft. A block 11 of these dimensions when filled with water will weigh slightly over 1000 lb. Unfilled, each block 11 will weigh 50 lb. or less, light enough for two people to lift and maneuver.

The material properties of the plastic from which block 11 is made should include relative stiffness and resistance to cold weather deterioration. Note that each additional tier adds roughly 28 lb./in.² of compressive stress on the material comprising a block 11 having the 0.25 in. wall thicknesses shown. The block 11 material must be able to easily support such loads under what are often mechanically stressful conditions.

FIG. 3 shows details of the structure of a levee wall 10 constructed on a ground surface 54. Surface 48 shows the level of restrained water on the wet side 16 of levee wall 10. For 2 ft. high blocks 11, wall 10 as shown in FIG. 3 is 14 ft. high.

Wall 10 of FIG. 3 has seven tiers 10A-10G, although more or fewer tiers may be present. Each of the tiers 10B-10G has one less row of blocks 11 than the tier on which it sits. Each of the tiers 10B-10G overlaps one half of each of the two outside rows of blocks 11 in the tier on which it sits. (A row of blocks 11 extends perpendicular to the plane of FIG. 3. Tier 10A has eight rows, for example.)

To prevent seepage of water through a levee wall 10, plastic sheeting 45 may lie along the wet side 16 of wall 10. The top end of sheeting 45 may fit under the top tier 10G.

A pile of sandbags 51 lies on a part of the plastic sheeting 45 on surface 54 and extending away from levee wall 10, and also against the wet side 16, which provides support for sandbags 51. This construction requires many fewer sandbags 51 for a given levee wall 10 height than does a levee wall comprising only sandbags. Sandbags 51 stabilize the base of levee wall 10 and reduce seepage of water under the base of levee wall 10.

FIG. 4 shows the relationship between the blocks 10 in tier 11A and in tier 11B for a portion of a levee wall 10, and how a tier 11A, etc. comprises a plurality of interconnected blocks 11 extending along both the length and width of a wall 10. One sees the filler holes 27 in each of the blocks 11 forming tier 10A. Dotted line squares 42 indicate the position that the blocks comprising tier 11B occupy. The recess 30 of each block in tier 10B vertically aligns with a filler hole 27 in a block in tier 10A. A pin 37 (FIG. 2) fits into the recess 30 of one block 11 and the filler hole 27 of the block beneath that recess 30. Pins 37 collectively cooperate to maintain the position of each tier 10B-10G with respect to the tier on which it rests. Pins 37 and filler holes 27 form cooperating inter-tier connection features on the bottoms and tops respectively of blocks 11 to connect the successive tiers 10A, etc. of blocks 11.

It is likely that the outside blocks 11 of successive tiers 10B-10G need not overlap by 50% as shown in FIGS. 3 and 4 to provide sufficient mass to resist the pressure of water standing along a side of wall 10. By properly sizing the depth of one row of blocks 11 along the length (as opposed to the depth) of each tier 10B-10G, the overlap on the outside blocks 11 of the overlying tier can be increased to 67% or 75% for example. This will likely require special positioning of the inter-tier connection features as well.

Increasing the overlap to 67% or 75% eliminates a number of unneeded interior blocks 11 for a given number of tiers 10B-10G. FIG. 7 shows a 75% overlap from tier 10A′ to tier 10B′. This increased overlap arises from a void 58 in tier 10B′. Note that this design provides four tiers 10A′-10D′ using only eight blocks 11 rather than 10 blocks 11 as shown for tiers 10E-10H in FIG. 3.

Overlaps of greater than 50% require differences in the positions of inter-tier connection features to align them in upper and lower adjacent tiers 10A′-10D′. It is possible that efficiency will require that tops and bottoms of each block 11 have a number of sets of inter-tier connection features, but that only one set is used, depending on the tier 10A′-10D′ in which the block 11 is used. For example, FIG. 7 shows two features 62 in the nature of recesses 30 shown in FIG. 4 in the bottom of each block 11, and three features 64 in the top of each block 11. Pins 37 fit in one feature 62 of one block 11 and an aligned feature 64 of another block 11.

Construction of a levee wall 11 may start at one end by positioning unfilled blocks 11 forming a portion of several rows for tier 11A. Each block 11 of course must interlock with the adjacent blocks 11 to connect all of the blocks 11 in tier 10A together.

After a block 11 has been position in tier 10A, it may be filled with water. As soon as several blocks 11 have been laid in the row of tier 10A nearest to the side on which restrained water is expected, plastic sheeting 45 is positioned and sandbags 51 placed on the sheeting. After all of the rows forming tier 10A have been started, then placement and filling of the blocks 11 forming tier 10B can start.

This process continues for as many tiers as are required. One can see that this process lends itself to a number of workers simultaneously constructing such a levee wall 10. Some can be placing blocks 11, while others handle filling of blocks 11 and placement of the sheeting 45 and sandbags 51.

The weight of upper tiers 10F and 10G for example, distort blocks in the lower tiers 10A and 10B for example, reducing gaps between individual blocks 11. Such distortion further limits infiltration and leakage of water through wall 10.

Additional tiers can easily be added on the dry side of levee 10 should water level projections warrant. Workers can climb up the blocks 10 already emplaced to place the empty blocks 10. Then as blocks 10 are placed, water is pumped into the placed blocks 10 through their filler holes 27.

Workers disassemble a wall 10 when water level 48 recedes by substantially reversing the wall 10 assembly steps. Workers remove individual drain plugs 15 from blocks 10 on the top tiers and then remove individual blocks 10 after draining ends. Two drain plugs 15 allow access to one or the other of drain plugs 15 in blocks 11 from either side of a tier 10A-10G. If a drain plug 15 is not accessible on either side, then a wall 10 can be disassembled from only one side of each tier 10A-10G.

Blocks 10 can be stored outside if desirable awaiting another threatened flood. Both assembly and disassembly of a wall 10 is less labor intensive than a sandbag wall.

FIG. 6 shows a wall 10′ having a construction suitable for use on a sloping surface 54. Sandbags 51 level the surface 54 on which tier 10A′ sits.

Proper esthetic design of blocks 11 may allow their use as a permanent, inexpensive retaining wall. This is likely to be truer in more temperate climates where freezing is infrequent or nonexistent. 

1. A hollow block in the form of a rectangular parallelepiped to be filled with water, for joining with a plurality of with similar water-filled blocks to form a flood barrier, said block having first through fourth sides, a top, and a bottom, wherein the first and third sides have connection features that connect with features on the first and third sides of adjacent blocks to form a wall of connected blocks, and wherein the top and bottom of said block has an inter-tier connection feature suitable for mating with an inter-tier connection feature on the adjacent top or bottom of a similar block.
 2. The block of claim 1, including on its bottom, a plurality of inter-tier connection features, and the inter-tier connection feature in the block's top is structured to mate with an inter-tier connection feature of a similar block in an adjacent upper tier of a flood barrier.
 3. The block of claim 2, wherein an inter-tier connection feature of a block comprises a filler hole in the block's top.
 4. The block of claim 2, wherein the position of an inter-tier connection feature on a first block aligns with a similar adjacent second block at a position producing overlap of the first and second blocks that is greater than 50%.
 5. The block of claim 4, including a pin fitting in an inter-tier connection of each of the first and second blocks.
 6. The block of claim 1, wherein the second and fourth sides thereof have connection features that connect with features on the second and fourth sides of adjacent blocks to allow forming a wall of interlocked blocks comprising a plurality of rows of blocks.
 7. A plurality of the blocks of claim 6 assembled into a wall, and having a plurality of tiers, each tier having a plurality of rows of blocks.
 9. The block of claim 8, wherein the stiffening wall has an opening providing communication between spaces defined by the stiffening wall.
 10. The block of claim 8, including a pair of internal stiffening walls extending between opposite sidewalls and to the top and bottom of the block.
 11. The block of claim 1, wherein two opposing sides each have a drain plug near the block bottom.
 12. The block of claim 1, including an internal stiffening wall extending between opposite sidewalls and to the top and bottom of the block. 